Respiration (4.2)

Question 1

Cellular respiration is an (…) reaction which is (…) occurring in (…) (+ releases energy)

Answer 1

exothermic

continuously

living cells

Question 2

The energy transferred supplies (…) the (…) needed for (…)

Answer 2

all

energy

living processes

Question 3

What are the two types of respiration, used to transfer energy

Answer 3

aerobically (using oxygen)

anaerobically (without oxygen)

Question 4

Is oxygen needed in anaerobic respiration?

Answer 4

No - but it is in aerobic

Question 5

Compare glucose breakdown in aerobic and anaerobic respiration

Answer 5

Aerobic - complete glucose breakdown

Anaerobic - incomplete glucose breakdown

Question 6

How much energy is released in aerobic and anaerobic respiration?

Answer 6

Aerobic - relatively large amount

Anaerobic - smaller amount, but quicker (than aerobic)

Question 7

3 things

Organisms need energy for…

Answer 7

• chemical reactions to build larger molecules (to build carbohydrates/proteins/lipids from products of photosynthesis in plants and digestion in animals)
• movement (energy needed for muscle contraction in animals, transportation of substances in phloem in plants)
• keeping (body) warm (distributed by blood to whole body, maintaining conditions for optimum function)

Question 8

What is the equation for aerobic respiration?

Answer 8

glucose + oxygen ⇢ carbon dioxide + water

Question 9

What is the equation for anaerobic respiration in muscles?

Answer 9

glucose ⇢ lactic acid

Question 10

What is the equation for anaerobic respiration in plant and yeast cells?

Answer 10

glucose ⇢ ethanol + carbon dioxide

Question 11

Why is much less energy transferred in anaerobic respiration than aerobic?

Answer 11

because the oxidation of glucose is incomplete in anaerobic respiration

Question 12

What is anaerobic respiration in yeast cells called?

Answer 12

fermentation

Question 13

What is the use/importance of fermentation?

Answer 13

It has economic importance in the manufacture of bread and alcoholic drinks

Question 14

What is metabolism?

Answer 14

the sum of all the reactions in a cell or the body

Question 15

The energy transferred by respiration in cells is used by the organism for which processes?

Answer 15

the continual enzyme controlled processes of metabolism that synthesise new molecules

Question 16

Give 5 examples of metabolism

Answer 16

• conversion of glucose to starch, glycogen and cellulose
• the formation of lipid molecules from a molecule of glycerol and three molecules of fatty acids
• the use of glucose and nitrate ions to form amino acids which in turn are used to synthesise proteins
• respiration
• breakdown of excess proteins to form urea for excretion

Question 17

That metabolism includes reactions that build up…

and reactions that break down…

Answer 17

larger molecules from smaller ones (forms carbohydrates, proteins and lipids)

larger molecules into smaller ones (forms sugars, amino acids, fatty acids and glycerol)